THE INTERNATIONAL JAGUAR 'S'-TYPE REGISTER FORUM

Thanks Nigel I will look in to that.

No not an electronic distributor but a Luminition Magnatronic system. I think the problem is the timing, I have fitted a series 3 engine in it but have retained the series 1 distributor and the series 1 timing of 8 deg BTDC. After interweb research it looks like the 3 engine requires 18 deg with less centrifugal advance. All this only started showing up when I removed the horrible XJ AED that was leaking and over fuelling that was masking the timing problem. I'll get back on very soon but had to call a halt to working on it as I went down with heat stroke working on it in the sun all day compounded by standing over a red hot engine.

I was looking at a friend's custom Mk2 Transit yesterday, he has fitted the same distributor you're getting and he really rates it. The only problem he had was a couple of weeks ago when the rota arm packed up, looking at it afterwards and testing it we both agreed it was crap and best replaced with something of better quality, so suggest you do,the same before fitting.

Electrical problems are easy when the thing does not work as you just keep changing things until it does but when its an intermittent fault as mine started out as they can be a real pain to track down. Fingers crossed mine will be solved on Tuesday.
Do you have an electronic distributor on your XJ6 Nigel?

I'm chasing a similar fault on my XJ, it was going to go to Wroxall last week but only got 300yards from my drive when the engine cut out. Got it started and limped back home to change cars to the S Type. Previous day did a 25 mile run in it with no problems. So far changed fuel filter, coil, spark plugs and a host of other stuff checked but engine won't rev beyond 2k rpm.

Well I think my decision has been made for me.
Earlier this week I started to get a stutter/cut out on the ignition under load. Annoying but not at that point fatal.
Friday I had time so decided to do some tests on the electrical side, one thing at a time, to try and track down the fault.
Changed the plugs although I knew it was not them as all six would not cut out all at once. Ran fine but still with the stutter/cut out.
Changed the coil for a new one, took it for a drive and the problem remained. Two mins later at home on the drive and the car would not restart. No spark at High or low even though I had power going in to the distributor and the earth was fine.
Phoned up SimonBBC whom I bought the system off four years ago and gave them the symptoms. They basically confirmed that the electronic distributor had broken down but there was no way of testing it unless I sent it back.
So a replacement positive earth insert module is about £40. A complete negative earth distributor is £65. The alternator conversion which sits in the original dynamo housing and has the drive off the back for the power steering pump is £145 which then allows me to convert to Negative earth. £215 for the lot with postage but it will not be here until Tuesday.
Always happens on a Friday and this weekend is the big Powderham classic car rally over two days which I was going to attend. Still it gave me the opportunity to take the classic bike along instead and as the weather was great it made a change for a nice ride out. Full leathers made it bloody hot on the bike though.
Once the bits arrive I will get them fitted and write a thread about the conversion to this new alternator and converting from Positive to Negative earth.

Actually John the change over to negative earth is very simple and has been discussed on the old forum at length. This is the link http://www.jagstyperegister.com/forum/v ... f=15&t=144
Most Jaguar clocks no longer work and mine is one of those so no problem with that. All the other dials do not need to be changed other than the Amp Meter which needs to be reversed. If you were running the generator that would have to be re polarized but the new alternator would already be running negative earth. The fuel pumps need swapping over and things like the radio but otherwise its a fairly straightforward operation. As for the plugs as the coil is swapped over the flow of electricity through the plugs should remain the same but would not really matter if it was reversed.
I just have to figure out if the swap over has enough benefits to justify the cost. At well over £600 three years ago it was not but now these units are getting cheaper £200 would allow my to change over to an alternator and have negative earth.

If you convert to negative earth would you need to change other electric items, such the clock , rev counter, coil ?. I did read along time ago that the direction of flow of the spark plugs is reversed, not sure how that works or if it is correct. Just as an add on I think that the power steering to my car was a retro fit going by the chassis number

Regards John

1B1257BW

Hi Rob, I did this change way back in the 70's. The problem I had was the Kenlow fan was draining the battery especially at night with the lights on sitting in London traffic, the old dynamo couldn't keep up and once left me stranded in Chelsea late one night in the rain. I fitted a 18ACR alternator and an XJ6 battery in the boot - never had any more problems after that including crawling through the Los Angeles traffic at rush hour down to Long Beach.

As far as the - or + earth, it gave me the opportunity to fit an updated stereo system and could later on use any - earth gadgets as required. For me it was well worth doing but in your circumstances I'd keep my money in my pocket.

Interesting set up you have there John. I have the original PAS pump set up which runs off the back of the generator. I had wanted to change to an alternator previously during my rebuild but I could not find one with a drive on the back for the PAS pump. These alternators by Dynalite have the same housing as the original generator and the same drive off the back so I would not need to change the original PAS pump. They have come down in price since I first saw them at over £600 so at £160 they are now in my price range. Just wanted to know from others experience if running an alternator and negative earth gives you any benefits over the original generator and positive earth. My system is working fine as it is so there is not a need to change. Just curious.

Hi Rob
I had a look at some pictures of my power steering set up, and the power steering pump power is taken off is from a duel grooved pulley on the crankshaft. This of course would mean that either a different pump is used or the original modified to take a pulley. when I acquired my car the original pump had been modified but it now has a pump used from an early Range rover that I bought off ebay. If you you don't mind me saying it seems like an awful lot of work and cost particularly if you don't have any issues. I suppose you could change the pump for a pump/motor and attach it to the inner wing. Some of the small cars use this in the past . As you can see this picture shows an oil leak and that is why the pump was replaced after three attempts to cue the problem.

Regards John
1B1257BW
1972 Rover P6